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			<h1>Java 多态</h1>
<hr>

<p>多态是同一个行为具有多个不同表现形式或形态的能力。</p>
<p>多态就是同一个接口，使用不同的实例而执行不同操作，如图所示：</p>
</p>
<p><img decoding="async" width="70%" src="https://www.runoob.com/wp-content/uploads/2013/12/java-polymorphism-111.png"></p>
<p>多态性是对象多种表现形式的体现。</p>

<blockquote>
<p>现实中，比如我们按下 F1 键这个动作：
</p>
<ul><li>
如果当前在 Flash 界面下弹出的就是 AS 3 的帮助文档；</li><li>如果当前在 Word 下弹出的就是 Word 帮助；</li><li>在 Windows 下弹出的就是 Windows 帮助和支持。</li></ul><p>同一个事件发生在不同的对象上会产生不同的结果。</p>
</blockquote>
<h3>
多态的优点
</h3><ul><li>
1. 消除类型之间的耦合关系</li><li>
2. 可替换性</li><li>
3. 可扩充性</li><li>
4. 接口性</li><li>
5. 灵活性</li><li>
6. 简化性</li></ul>

<h3>多态存在的三个必要条件</h3>
<ul><li>继承</li><li>重写</li><li>父类引用指向子类对象：<span class="marked">Parent p = new Child();</span></li></ul>
<p><img decoding="async" width="70%" src="https://www.runoob.com/wp-content/uploads/2013/12/2DAC601E-70D8-4B3C-86CC-7E4972FC2466.jpg"></p>
<div class="example"><div class="example_code">
<span style="color: #000000; font-weight: bold;">class</span> <span style="color: #003399;">Shape</span> <span style="color: #009900;">&#123;</span><br />
&nbsp; &nbsp; <span style="color: #000066; font-weight: bold;">void</span> draw<span style="color: #009900;">&#40;</span><span style="color: #009900;">&#41;</span> <span style="color: #009900;">&#123;</span><span style="color: #009900;">&#125;</span><br />
<span style="color: #009900;">&#125;</span><br />
&nbsp; <br />
<span style="color: #000000; font-weight: bold;">class</span> Circle <span style="color: #000000; font-weight: bold;">extends</span> <span style="color: #003399;">Shape</span> <span style="color: #009900;">&#123;</span><br />
&nbsp; &nbsp; <span style="color: #000066; font-weight: bold;">void</span> draw<span style="color: #009900;">&#40;</span><span style="color: #009900;">&#41;</span> <span style="color: #009900;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #003399;">System</span>.<span style="color: #006633;">out</span>.<span style="color: #006633;">println</span><span style="color: #009900;">&#40;</span><span style="color: #0000ff;">&quot;Circle.draw()&quot;</span><span style="color: #009900;">&#41;</span><span style="color: #339933;">;</span><br />
&nbsp; &nbsp; <span style="color: #009900;">&#125;</span><br />
<span style="color: #009900;">&#125;</span><br />
&nbsp; <br />
<span style="color: #000000; font-weight: bold;">class</span> Square <span style="color: #000000; font-weight: bold;">extends</span> <span style="color: #003399;">Shape</span> <span style="color: #009900;">&#123;</span><br />
&nbsp; &nbsp; <span style="color: #000066; font-weight: bold;">void</span> draw<span style="color: #009900;">&#40;</span><span style="color: #009900;">&#41;</span> <span style="color: #009900;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #003399;">System</span>.<span style="color: #006633;">out</span>.<span style="color: #006633;">println</span><span style="color: #009900;">&#40;</span><span style="color: #0000ff;">&quot;Square.draw()&quot;</span><span style="color: #009900;">&#41;</span><span style="color: #339933;">;</span><br />
&nbsp; &nbsp; <span style="color: #009900;">&#125;</span><br />
<span style="color: #009900;">&#125;</span><br />
&nbsp; <br />
<span style="color: #000000; font-weight: bold;">class</span> Triangle <span style="color: #000000; font-weight: bold;">extends</span> <span style="color: #003399;">Shape</span> <span style="color: #009900;">&#123;</span><br />
&nbsp; &nbsp; <span style="color: #000066; font-weight: bold;">void</span> draw<span style="color: #009900;">&#40;</span><span style="color: #009900;">&#41;</span> <span style="color: #009900;">&#123;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; <span style="color: #003399;">System</span>.<span style="color: #006633;">out</span>.<span style="color: #006633;">println</span><span style="color: #009900;">&#40;</span><span style="color: #0000ff;">&quot;Triangle.draw()&quot;</span><span style="color: #009900;">&#41;</span><span style="color: #339933;">;</span><br />
&nbsp; &nbsp; <span style="color: #009900;">&#125;</span><br />
<span style="color: #009900;">&#125;</span><br />
</div></div>

<p>当使用多态方式调用方法时，首先检查父类中是否有该方法，如果没有，则编译错误；如果有，再去调用子类的同名方法。</p>
<p>多态的好处：可以使程序有良好的扩展，并可以对所有类的对象进行通用处理。</p>
<p>以下是一个多态实例的演示，详细说明请看注释：</p>
<div class="example">
<h2 class="example">Test.java 文件代码：</h2>
<div class="example_code">
<div class="hl-main"><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">Test</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
    </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">static</span><span class="hl-code"> </span><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">main</span><span class="hl-brackets">(</span><span class="hl-identifier">String</span><span class="hl-brackets">[</span><span class="hl-brackets">]</span><span class="hl-code"> </span><span class="hl-identifier">args</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
      </span><span class="hl-identifier">show</span><span class="hl-brackets">(</span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">Cat</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-brackets">)</span><span class="hl-code">;  </span><span class="hl-comment">//</span><span class="hl-comment"> 以 Cat 对象调用 show 方法</span><span class="hl-comment"></span><span class="hl-code">
      </span><span class="hl-identifier">show</span><span class="hl-brackets">(</span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">Dog</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-brackets">)</span><span class="hl-code">;  </span><span class="hl-comment">//</span><span class="hl-comment"> 以 Dog 对象调用 show 方法</span><span class="hl-comment"></span><span class="hl-code">
                
      </span><span class="hl-identifier">Animal</span><span class="hl-code"> </span><span class="hl-identifier">a</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">Cat</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;  </span><span class="hl-comment">//</span><span class="hl-comment"> 向上转型  </span><span class="hl-comment"></span><span class="hl-code">
      </span><span class="hl-identifier">a</span><span class="hl-code">.</span><span class="hl-identifier">eat</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;               </span><span class="hl-comment">//</span><span class="hl-comment"> 调用的是 Cat 的 eat</span><span class="hl-comment"></span><span class="hl-code">
      </span><span class="hl-identifier">Cat</span><span class="hl-code"> </span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-brackets">(</span><span class="hl-identifier">Cat</span><span class="hl-brackets">)</span><span class="hl-identifier">a</span><span class="hl-code">;        </span><span class="hl-comment">//</span><span class="hl-comment"> 向下转型  </span><span class="hl-comment"></span><span class="hl-code">
      </span><span class="hl-identifier">c</span><span class="hl-code">.</span><span class="hl-identifier">work</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;        </span><span class="hl-comment">//</span><span class="hl-comment"> 调用的是 Cat 的 work</span><span class="hl-comment"></span><span class="hl-code">
  </span><span class="hl-brackets">}</span><span class="hl-code">  
            
    </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">static</span><span class="hl-code"> </span><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">show</span><span class="hl-brackets">(</span><span class="hl-identifier">Animal</span><span class="hl-code"> </span><span class="hl-identifier">a</span><span class="hl-brackets">)</span><span class="hl-code">  </span><span class="hl-brackets">{</span><span class="hl-code">
      </span><span class="hl-identifier">a</span><span class="hl-code">.</span><span class="hl-identifier">eat</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;  
        </span><span class="hl-comment">//</span><span class="hl-comment"> 类型判断</span><span class="hl-comment"></span><span class="hl-code">
        </span><span class="hl-reserved">if</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-identifier">a</span><span class="hl-code"> </span><span class="hl-reserved">instanceof</span><span class="hl-code"> </span><span class="hl-identifier">Cat</span><span class="hl-brackets">)</span><span class="hl-code">  </span><span class="hl-brackets">{</span><span class="hl-code">  </span><span class="hl-comment">//</span><span class="hl-comment"> 猫做的事情 </span><span class="hl-comment"></span><span class="hl-code">
            </span><span class="hl-identifier">Cat</span><span class="hl-code"> </span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-brackets">(</span><span class="hl-identifier">Cat</span><span class="hl-brackets">)</span><span class="hl-identifier">a</span><span class="hl-code">;  
            </span><span class="hl-identifier">c</span><span class="hl-code">.</span><span class="hl-identifier">work</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;  
        </span><span class="hl-brackets">}</span><span class="hl-code"> </span><span class="hl-reserved">else</span><span class="hl-code"> </span><span class="hl-reserved">if</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-identifier">a</span><span class="hl-code"> </span><span class="hl-reserved">instanceof</span><span class="hl-code"> </span><span class="hl-identifier">Dog</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code"> </span><span class="hl-comment">//</span><span class="hl-comment"> 狗做的事情 </span><span class="hl-comment"></span><span class="hl-code">
            </span><span class="hl-identifier">Dog</span><span class="hl-code"> </span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-brackets">(</span><span class="hl-identifier">Dog</span><span class="hl-brackets">)</span><span class="hl-identifier">a</span><span class="hl-code">;  
            </span><span class="hl-identifier">c</span><span class="hl-code">.</span><span class="hl-identifier">work</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;  
        </span><span class="hl-brackets">}</span><span class="hl-code">  
    </span><span class="hl-brackets">}</span><span class="hl-code">  
</span><span class="hl-brackets">}</span><span class="hl-code">
 
</span><span class="hl-reserved">abstract</span><span class="hl-code"> </span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">Animal</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">  
    </span><span class="hl-reserved">abstract</span><span class="hl-code"> </span><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">eat</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;  
</span><span class="hl-brackets">}</span><span class="hl-code">  
  
</span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">Cat</span><span class="hl-code"> </span><span class="hl-reserved">extends</span><span class="hl-code"> </span><span class="hl-identifier">Animal</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">  
    </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">eat</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">  
        </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">println</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">吃鱼</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;  
    </span><span class="hl-brackets">}</span><span class="hl-code">  
    </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">work</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">  
        </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">println</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">抓老鼠</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;  
    </span><span class="hl-brackets">}</span><span class="hl-code">  
</span><span class="hl-brackets">}</span><span class="hl-code">  
  
</span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">Dog</span><span class="hl-code"> </span><span class="hl-reserved">extends</span><span class="hl-code"> </span><span class="hl-identifier">Animal</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">  
    </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">eat</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">  
        </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">println</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">吃骨头</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;  
    </span><span class="hl-brackets">}</span><span class="hl-code">  
    </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">work</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">  
        </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">println</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">看家</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;  
    </span><span class="hl-brackets">}</span><span class="hl-code">  
</span><span class="hl-brackets">}</span></div>
</div>
</div>
<p>执行以上程序，输出结果为：</p>
<pre>
吃鱼
抓老鼠
吃骨头
看家
吃鱼
抓老鼠
</pre>

<hr>
<h2>虚函数</h2>
<p>虚函数的存在是为了多态。</p>

<p>Java 中其实没有虚函数的概念，它的普通函数就相当于 C++ 的虚函数，动态绑定是Java的默认行为。如果 Java 中不希望某个函数具有虚函数特性，可以加上 final 关键字变成非虚函数。</p>
<h3>重写</h3>
<p>我们将介绍在 Java 中，当设计类时，被重写的方法的行为怎样影响多态性。</p><p>
我们已经讨论了方法的重写，也就是子类能够重写父类的方法。</p><p>
当子类对象调用重写的方法时，调用的是子类的方法，而不是父类中被重写的方法。</p><p>
要想调用父类中被重写的方法，则必须使用关键字 <strong>super</strong>。</p>
<div class="example">
<h2 class="example">Employee.java 文件代码：</h2>
<div class="example_code">
<div class="hl-main"><span class="hl-comment">/*</span><span class="hl-comment"> 文件名 : Employee.java </span><span class="hl-comment">*/</span><span class="hl-code">
</span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">Employee</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
   </span><span class="hl-reserved">private</span><span class="hl-code"> </span><span class="hl-identifier">String</span><span class="hl-code"> </span><span class="hl-identifier">name</span><span class="hl-code">;
   </span><span class="hl-reserved">private</span><span class="hl-code"> </span><span class="hl-identifier">String</span><span class="hl-code"> </span><span class="hl-identifier">address</span><span class="hl-code">;
   </span><span class="hl-reserved">private</span><span class="hl-code"> </span><span class="hl-types">int</span><span class="hl-code"> </span><span class="hl-identifier">number</span><span class="hl-code">;
   </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-identifier">Employee</span><span class="hl-brackets">(</span><span class="hl-identifier">String</span><span class="hl-code"> </span><span class="hl-identifier">name</span><span class="hl-code">, </span><span class="hl-identifier">String</span><span class="hl-code"> </span><span class="hl-identifier">address</span><span class="hl-code">, </span><span class="hl-types">int</span><span class="hl-code"> </span><span class="hl-identifier">number</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
      </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">println</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">Employee 构造函数</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
      </span><span class="hl-reserved">this</span><span class="hl-code">.</span><span class="hl-identifier">name</span><span class="hl-code"> = </span><span class="hl-identifier">name</span><span class="hl-code">;
      </span><span class="hl-reserved">this</span><span class="hl-code">.</span><span class="hl-identifier">address</span><span class="hl-code"> = </span><span class="hl-identifier">address</span><span class="hl-code">;
      </span><span class="hl-reserved">this</span><span class="hl-code">.</span><span class="hl-identifier">number</span><span class="hl-code"> = </span><span class="hl-identifier">number</span><span class="hl-code">;
   </span><span class="hl-brackets">}</span><span class="hl-code">
   </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">mailCheck</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
      </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">println</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">邮寄支票给： </span><span class="hl-quotes">&quot;</span><span class="hl-code"> + </span><span class="hl-reserved">this</span><span class="hl-code">.</span><span class="hl-identifier">name</span><span class="hl-code">
       + </span><span class="hl-quotes">&quot;</span><span class="hl-string"> </span><span class="hl-quotes">&quot;</span><span class="hl-code"> + </span><span class="hl-reserved">this</span><span class="hl-code">.</span><span class="hl-identifier">address</span><span class="hl-brackets">)</span><span class="hl-code">;
   </span><span class="hl-brackets">}</span><span class="hl-code">
   </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-identifier">String</span><span class="hl-code"> </span><span class="hl-identifier">toString</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
      </span><span class="hl-reserved">return</span><span class="hl-code"> </span><span class="hl-identifier">name</span><span class="hl-code"> + </span><span class="hl-quotes">&quot;</span><span class="hl-string"> </span><span class="hl-quotes">&quot;</span><span class="hl-code"> + </span><span class="hl-identifier">address</span><span class="hl-code"> + </span><span class="hl-quotes">&quot;</span><span class="hl-string"> </span><span class="hl-quotes">&quot;</span><span class="hl-code"> + </span><span class="hl-identifier">number</span><span class="hl-code">;
   </span><span class="hl-brackets">}</span><span class="hl-code">
   </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-identifier">String</span><span class="hl-code"> </span><span class="hl-identifier">getName</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
      </span><span class="hl-reserved">return</span><span class="hl-code"> </span><span class="hl-identifier">name</span><span class="hl-code">;
   </span><span class="hl-brackets">}</span><span class="hl-code">
   </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-identifier">String</span><span class="hl-code"> </span><span class="hl-identifier">getAddress</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
      </span><span class="hl-reserved">return</span><span class="hl-code"> </span><span class="hl-identifier">address</span><span class="hl-code">;
   </span><span class="hl-brackets">}</span><span class="hl-code">
   </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">setAddress</span><span class="hl-brackets">(</span><span class="hl-identifier">String</span><span class="hl-code"> </span><span class="hl-identifier">newAddress</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
      </span><span class="hl-identifier">address</span><span class="hl-code"> = </span><span class="hl-identifier">newAddress</span><span class="hl-code">;
   </span><span class="hl-brackets">}</span><span class="hl-code">
   </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">int</span><span class="hl-code"> </span><span class="hl-identifier">getNumber</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
     </span><span class="hl-reserved">return</span><span class="hl-code"> </span><span class="hl-identifier">number</span><span class="hl-code">;
   </span><span class="hl-brackets">}</span><span class="hl-code">
</span><span class="hl-brackets">}</span></div>
</div>
</div>
<p>假设下面的类继承Employee类：</p>
<div class="example">
<h2 class="example">Salary.java 文件代码：</h2>
<div class="example_code">
<div class="hl-main"><span class="hl-comment">/*</span><span class="hl-comment"> 文件名 : Salary.java </span><span class="hl-comment">*/</span><span class="hl-code">
</span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">Salary</span><span class="hl-code"> </span><span class="hl-reserved">extends</span><span class="hl-code"> </span><span class="hl-identifier">Employee</span><span class="hl-code">
</span><span class="hl-brackets">{</span><span class="hl-code">
   </span><span class="hl-reserved">private</span><span class="hl-code"> </span><span class="hl-types">double</span><span class="hl-code"> </span><span class="hl-identifier">salary</span><span class="hl-code">; </span><span class="hl-comment">//</span><span class="hl-comment"> 全年工资</span><span class="hl-comment"></span><span class="hl-code">
   </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-identifier">Salary</span><span class="hl-brackets">(</span><span class="hl-identifier">String</span><span class="hl-code"> </span><span class="hl-identifier">name</span><span class="hl-code">, </span><span class="hl-identifier">String</span><span class="hl-code"> </span><span class="hl-identifier">address</span><span class="hl-code">, </span><span class="hl-types">int</span><span class="hl-code"> </span><span class="hl-identifier">number</span><span class="hl-code">, </span><span class="hl-types">double</span><span class="hl-code"> </span><span class="hl-identifier">salary</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
       </span><span class="hl-reserved">super</span><span class="hl-brackets">(</span><span class="hl-identifier">name</span><span class="hl-code">, </span><span class="hl-identifier">address</span><span class="hl-code">, </span><span class="hl-identifier">number</span><span class="hl-brackets">)</span><span class="hl-code">;
       </span><span class="hl-identifier">setSalary</span><span class="hl-brackets">(</span><span class="hl-identifier">salary</span><span class="hl-brackets">)</span><span class="hl-code">;
   </span><span class="hl-brackets">}</span><span class="hl-code">
   </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">mailCheck</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
       </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">println</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">Salary 类的 mailCheck 方法 </span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
       </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">println</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">邮寄支票给：</span><span class="hl-quotes">&quot;</span><span class="hl-code"> + </span><span class="hl-identifier">getName</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">
       + </span><span class="hl-quotes">&quot;</span><span class="hl-string"> ，工资为：</span><span class="hl-quotes">&quot;</span><span class="hl-code"> + </span><span class="hl-identifier">salary</span><span class="hl-brackets">)</span><span class="hl-code">;
   </span><span class="hl-brackets">}</span><span class="hl-code">
   </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">double</span><span class="hl-code"> </span><span class="hl-identifier">getSalary</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
       </span><span class="hl-reserved">return</span><span class="hl-code"> </span><span class="hl-identifier">salary</span><span class="hl-code">;
   </span><span class="hl-brackets">}</span><span class="hl-code">
   </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">setSalary</span><span class="hl-brackets">(</span><span class="hl-types">double</span><span class="hl-code"> </span><span class="hl-identifier">newSalary</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
       </span><span class="hl-reserved">if</span><span class="hl-brackets">(</span><span class="hl-identifier">newSalary</span><span class="hl-code"> &gt;= </span><span class="hl-number">0</span><span class="hl-number">.0</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
          </span><span class="hl-identifier">salary</span><span class="hl-code"> = </span><span class="hl-identifier">newSalary</span><span class="hl-code">;
       </span><span class="hl-brackets">}</span><span class="hl-code">
   </span><span class="hl-brackets">}</span><span class="hl-code">
   </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">double</span><span class="hl-code"> </span><span class="hl-identifier">computePay</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
      </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">println</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">计算工资，付给：</span><span class="hl-quotes">&quot;</span><span class="hl-code"> + </span><span class="hl-identifier">getName</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-brackets">)</span><span class="hl-code">;
      </span><span class="hl-reserved">return</span><span class="hl-code"> </span><span class="hl-identifier">salary</span><span class="hl-code">/</span><span class="hl-number">52</span><span class="hl-code">;
   </span><span class="hl-brackets">}</span><span class="hl-code">
</span><span class="hl-brackets">}</span></div>
</div>
</div>
<p>现在我们仔细阅读下面的代码，尝试给出它的输出结果：</p>
<div class="example">
<h2 class="example">VirtualDemo.java 文件代码：</h2>
<div class="example_code">
<div class="hl-main"><span class="hl-comment">/*</span><span class="hl-comment"> 文件名 : VirtualDemo.java </span><span class="hl-comment">*/</span><span class="hl-code">
</span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">VirtualDemo</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
   </span><span class="hl-reserved">public</span><span class="hl-code"> </span><span class="hl-types">static</span><span class="hl-code"> </span><span class="hl-types">void</span><span class="hl-code"> </span><span class="hl-identifier">main</span><span class="hl-brackets">(</span><span class="hl-identifier">String</span><span class="hl-code"> </span><span class="hl-brackets">[</span><span class="hl-brackets">]</span><span class="hl-code"> </span><span class="hl-identifier">args</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-brackets">{</span><span class="hl-code">
      </span><span class="hl-identifier">Salary</span><span class="hl-code"> </span><span class="hl-identifier">s</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">Salary</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">员工 A</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-quotes">&quot;</span><span class="hl-string">北京</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-number">3</span><span class="hl-code">, </span><span class="hl-number">3600</span><span class="hl-number">.00</span><span class="hl-brackets">)</span><span class="hl-code">;
      </span><span class="hl-identifier">Employee</span><span class="hl-code"> </span><span class="hl-identifier">e</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">Salary</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">员工 B</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-quotes">&quot;</span><span class="hl-string">上海</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-number">2</span><span class="hl-code">, </span><span class="hl-number">2400</span><span class="hl-number">.00</span><span class="hl-brackets">)</span><span class="hl-code">;
      </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">println</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">使用 Salary 的引用调用 mailCheck -- </span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
      </span><span class="hl-identifier">s</span><span class="hl-code">.</span><span class="hl-identifier">mailCheck</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
      </span><span class="hl-identifier">System</span><span class="hl-code">.</span><span class="hl-identifier">out</span><span class="hl-code">.</span><span class="hl-identifier">println</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-special">\n</span><span class="hl-string">使用 Employee 的引用调用 mailCheck--</span><span class="hl-quotes">&quot;</span><span class="hl-brackets">)</span><span class="hl-code">;
      </span><span class="hl-identifier">e</span><span class="hl-code">.</span><span class="hl-identifier">mailCheck</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
    </span><span class="hl-brackets">}</span><span class="hl-code">
</span><span class="hl-brackets">}</span></div>
</div>
</div>
<p>以上实例编译运行结果如下：</p>
<pre>
Employee 构造函数
Employee 构造函数
使用 Salary 的引用调用 mailCheck -- 
Salary 类的 mailCheck 方法 
邮寄支票给：员工 A ，工资为：3600.0

使用 Employee 的引用调用 mailCheck--
Salary 类的 mailCheck 方法 
邮寄支票给：员工 B ，工资为：2400.0
</pre>
<h3>例子解析</h3>
<ul><li>
<p>实例中，实例化了两个 Salary 对象：一个使用 Salary 引用 s，另一个使用 Employee 引用 e。</p></li><li>
<p>
当调用 s.mailCheck() 时，编译器在编译时会在 Salary 类中找到  mailCheck()，执行过程 JVM 就调用 Salary 类的 mailCheck()。</p></li><li>
<p>
e 是 Employee 的引用，但引用 e 最终运行的是 Salary 类的 mailCheck() 方法。</p>
</li><li>
<p>
在编译的时候，编译器使用 Employee 类中的 mailCheck() 方法验证该语句，
但是在运行的时候，Java虚拟机(JVM)调用的是 Salary 类中的 mailCheck() 方法。</p></li>
</ul>
<p>
以上整个过程被称为虚拟方法调用，该方法被称为虚拟方法。</p><p>
Java中所有的方法都能以这种方式表现，因此，重写的方法能在运行时调用，不管编译的时候源代码中引用变量是什么数据类型。</p>
<hr>
<h2>多态的实现方式</h2>
<h3>方式一：重写：
</h3>
这个内容已经在上一章节详细讲过，就不再阐述，详细可访问：<a href="../java/java-override-overload.html" target="_blank" rel="noopener noreferrer">Java 重写(Override)与重载(Overload)</a>。</p>
<h3>方式二：接口
</h3>
<ul><li><p>
1. 生活中的接口最具代表性的就是插座，例如一个三接头的插头都能接在三孔插座中，因为这个是每个国家都有各自规定的接口规则，有可能到国外就不行，那是因为国外自己定义的接口类型。</p></li><li><p>
2. java中的接口类似于生活中的接口，就是一些方法特征的集合，但没有方法的实现。具体可以看 <a href="../java/java-interfaces.html" target="_blank" rel="noopener noreferrer">java接口</a> 这一章节的内容。</p></li></ul>
<h3>
方式三：抽象类和抽象方法
</h3><p>
详情请看 <a href="../java/java-abstraction.html" target="_blank" rel="noopener noreferrer">Java抽象类</a> 章节。</p>
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<div id="postcomments"  style="display:none;" >
	<ol class="commentlist">
		<li class="comment even thread-even depth-1" id="comment-10507"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;小丫小石头</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;116***1009@qq.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="http://blog.csdn.net/kaiwii/article/details/8042488">&nbsp;&nbsp;参考地址</a></p></div><div id="runoobvote-id-10507" data-commid = "10507" class="upvotejs"><a class="upvote"></a> <span class="count">121</span></div></div><div class="comt-main" id="div-comment-10507"><p><strong>对于多态，可以总结以下几点：</strong>
</p><p>
一、使用父类类型的引用指向子类的对象； </p><p>
 二、该引用只能调用父类中定义的方法和变量； </p><p>
 三、如果子类中重写了父类中的一个方法，那么在调用这个方法的时候，将会调用子类中的这个方法；（动态连接、动态调用）; </p><p>
 四、变量不能被重写（覆盖），”重写“的概念只针对方法，如果在子类中”重写“了父类中的变量，那么在编译时会报错。 </p><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">小丫小石头</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;小丫小石头</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;116***1009@qq.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="http://blog.csdn.net/kaiwii/article/details/8042488">&nbsp;&nbsp;参考地址</a></p></div></span>6年前 (2017-03-29)</div></div></li><!-- #comment-## -->
<li class="comment odd alt thread-odd thread-alt depth-1" id="comment-13381"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;九刃</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;528***187@qq.com</p></div><div id="runoobvote-id-13381" data-commid = "13381" class="upvotejs"><a class="upvote"></a> <span class="count">44</span></div></div><div class="comt-main" id="div-comment-13381"><p><strong>类的属性变量是能重写（覆盖）</strong>
</p><pre>
class Animal{
   public int age;
   public void move(){
      System.out.println("动物可以移动");
   }
}
 
class Dog extends Animal{
   public double age;
   public void move(){
       age = 10.00;
      System.out.println("狗可以跑和走");
   }
   public void bark(){
      System.out.println("狗可以吠叫");
   }
}

class Cat extends Animal{
   public void move(){
       super.age = 3;
      System.out.println("猫可以跳");
   }
}
 
public class TestOverride{
   public static void main(String args[]){
      Animal a = new Animal(); // Animal 对象
      Animal b = new Dog(); // Dog 对象
      Dog c = new Dog();
      Cat d = new Cat();
      
      a.move();// 执行 Animal 类的方法
      b.move();//执行 Dog 类的方法
      c.move();//执行 Dog 类的方法
      d.move();//执行 Cat 类的方法
      Object aValue = a.age;
      Object bValue = b.age;
      Object cValue = c.age;
      System.out.println("The type of "+a.age+" is "+(aValue instanceof Double ? "double" : (aValue instanceof Integer ? "int" : "")));
      System.out.println("The type of "+b.age+" is "+(bValue instanceof Double ? "double" : (bValue instanceof Integer ? "int" : "")));
      System.out.println("The type of "+c.age+" is "+(cValue instanceof Double ? "double" : (cValue instanceof Integer ? "int" : "")));// 覆盖age属性
      System.out.println("The age of cat  is "+d.age);
     
   }
}</pre><p>
编译值：</p>
<pre>
动物可以移动
狗可以跑和走
狗可以跑和走
猫可以跳
The type of 0 is int
The type of 0 is int
The type of 10.0 is double
The age of cat  is 3
</pre><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">九刃</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;九刃</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;528***187@qq.com</p></div></span>6年前 (2017-06-27)</div></div></li><!-- #comment-## -->
<li class="comment even thread-even depth-1" id="comment-18865"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;xiaohau7988</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;107***2774@qq.com</p></div><div id="runoobvote-id-18865" data-commid = "18865" class="upvotejs"><a class="upvote"></a> <span class="count">13</span></div></div><div class="comt-main" id="div-comment-18865"><p>多态引用时，构造子类对象时的构造方法的调用顺序</p><p>1，先调用超类的构造方法，多重超类首先调用最远超类的方法；</p><p>2，然后再执行当前子类的构造方法；</p><p>调用时需要谨慎处理调用方法</p><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">xiaohau7988</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;xiaohau7988</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;107***2774@qq.com</p></div></span>6年前 (2017-10-15)</div></div></li><!-- #comment-## -->
<li class="comment odd alt thread-odd thread-alt depth-1" id="comment-28724"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;matthew</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;656***122@qq.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="../w3cnote/java-polymorphism.html">&nbsp;&nbsp;参考地址</a></p></div><div id="runoobvote-id-28724" data-commid = "28724" class="upvotejs"><a class="upvote"></a> <span class="count">33</span></div></div><div class="comt-main" id="div-comment-28724"><p><strong>多态的分类</strong></p>
<p>多态一般分为两种：重写式多态和重载式多态。</p>

<p><strong>重载式多态</strong>，也叫编译时多态。也就是说这种多态再编译时已经确定好了。重载大家都知道，方法名相同而参数列表不同的一组方法就是重载。在调用这种重载的方法时，通过传入不同的参数最后得到不同的结果。</p>



<blockquote><p>但是这里是有歧义的，有的人觉得不应该把重载也算作多态。因为很多人对多态的理解是：程序中定义的引用变量所指向的具体类型和通过该引用变量发出的方法调用在编程时并不确定，而是在程序运行期间才确定，这种情况叫做多态。 这个定义中描述的就是我们的第二种多态—重写式多态。并且，重载式多态并不是面向对象编程特有的，而多态却是面向对象三大特性之一（如果我说的不对，记得告诉我。。）。</p>

<p>我觉得大家也没有必要在定义上去深究这些，我的理解是：同一个行为具有多个不同表现形式或形态的能力就是多态，所以我认为重载也是一种多态，如果你不同意这种观点，我也接受。</p></blockquote>



<p><strong>重写式多态</strong>，也叫运行时多态。这种多态通过动态绑定（dynamic binding）技术来实现，是指在执行期间判断所引用对象的实际类型，根据其实际的类型调用其相应的方法。也就是说，只有程序运行起来，你才知道调用的是哪个子类的方法。 
这种多态通过函数的重写以及向上转型来实现，我们上面代码中的例子就是一个完整的重写式多态。我们接下来讲的所有多态都是重写式多态，因为它才是面向对象编程中真正的多态。</p>
<p><strong>更多内容参考：<a href="../w3cnote/java-polymorphism.html" target="_blank" rel="noopener nofollow">Java 中的多态</a></strong></p><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">matthew</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;matthew</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;656***122@qq.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="../w3cnote/java-polymorphism.html">&nbsp;&nbsp;参考地址</a></p></div></span>5年前 (2018-06-25)</div></div></li><!-- #comment-## -->
<li class="comment even thread-even depth-1" id="comment-34591"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;我是小萌新</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;239***9370@qq.com</p></div><div id="runoobvote-id-34591" data-commid = "34591" class="upvotejs"><a class="upvote"></a> <span class="count">31</span></div></div><div class="comt-main" id="div-comment-34591"><p>父类的属性变量（例如变量  int a）可以被继承，同时在子类中也会同时继承该变量（super.int a,继承的变量），子类中也可以再次声明一个同名（可以同类型）的变量（double a,自己声明的同名变量），两者可以同时存在。在输出时候根据对象的引用名输出，例如：</p>
<pre>class Animal{
    public int age;      //此处在Animal中定义类型为int，名为age的变量。
    public void move(){
        System.out.println("动物总是不安分");
    }
}
     
class Dog extends Animal{
    public double age;    //此处在Dog中定义新类型double,名为age的变量。当然int尝试也可以。 
    public void move(){
        age =10;
        System.out.println("狗跑的很快");
    }
}
class Cat extends Animal{
    public void move(){
        super.age = 3;   //此处继承age，并赋值为3.且该类中未重新定义变量。
        System.out.println("猫跳的很高");
    }
}     
public class DuiXiang03{
    public static void main(String args[]){
        Animal a = new Animal(); // Animal 对象
        Animal b = new Dog(); // Dog 对象
        Animal c =new Cat(); //Cat 对象
        Dog  d= new Dog();
        Cat  e= new Cat();

        a.move();//执行 Animal 类的方法
        b.move();//执行 Dog 类的方法
        c.move();//执行 Cat 类的方法
        d.move();//执行Dog 类的方法
        e.move();//执行 Cat 类的方法
        Object aValue = a.age;
        Object bValue = b.age;      // b.age有两个age值，一个是自定义的age值，一个是继承的age值
        Object cValue = c.age;     
        Object dValue = d.age;      // d.age有两个age值，一个是自定义的age值，一个是继承的age值
        Object eValue =e.age;
        System.out.println("The type of "+a.age+" is "+(aValue instanceof Double ? "double" : (aValue instanceof Integer ? "int" : "")));     // Animal 类中的 age 未被赋值
        System.out.println("The type of "+b.age+" is "+(bValue instanceof Double ? "double" : (bValue instanceof Integer ? "int" : "")));     // b.age有两个age值，输出取引用名为Animal的int类型值
        System.out.println("The type of "+c.age+" is "+(cValue instanceof Double ? "double" : (cValue instanceof Integer ? "int" : "")));     // c.age只有一个age值，是super所继承的Animal中的age值，再被赋值为3
        System.out.println("The type of "+d.age+" is "+(dValue instanceof Double ? "double" : (dValue instanceof Integer ? "int" : "")));     // d.age有两个age值，输出取引用名为Dog的double类型值
        System.out.println("The type of "+e.age+" is "+(eValue instanceof Double ? "double" : (eValue instanceof Integer ? "int" : "")));     // c.age只有一个age值，是super所继承的Animal中的age值，再被赋值为3
    }
}</pre>
<p>输出的结果为：</p>

<pre>动物总是不安分
狗跑的很快
猫跳的很高
狗跑的很快
猫跳的很高
The type of 0 is int
The type of 0 is int
The type of 3 is int
The type of 10.0 is double
The type of 3 is int</pre>
<div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">我是小萌新</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;我是小萌新</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;239***9370@qq.com</p></div></span>5年前 (2018-08-30)</div></div></li><!-- #comment-## -->
<li class="comment odd alt thread-odd thread-alt depth-1" id="comment-35864"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;Toniko</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;wdt***@163.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="https://www.icourse163.org/learn/ZJU-1001542001?tid=1002776001#/learn/content?type=detail&amp;id=1004061166&amp;sm=1">&nbsp;&nbsp;参考地址</a></p></div><div id="runoobvote-id-35864" data-commid = "35864" class="upvotejs"><a class="upvote"></a> <span class="count">21</span></div></div><div class="comt-main" id="div-comment-35864"><p>如果子类的方法覆盖了父类的方法，我们也说父类的那个方法在子类有了新的版本或者新的实现。覆盖的新版本具有与老版本相同的方法签名：相同的方法名称和参数表。因此，对于外界来说，子类并没有增加新的方法，仍然是在父类中定义过的那个方法。不同的是，这是一个新版本，所以通过子类的对象调用这个方法，执行的是子类自己的方法。</p>

<p>覆盖关系并不说明父类中的方法已经不存在了，而是当通过一个子类的对象调用这个方法时，子类中的方法取代了父类的方法，父类的这个方法被“覆盖”起来而看不见了。而当通过父类的对象调用这个方法时，实际上执行的仍然是父类中的这个方法。注意我们这里说的是对象而不是变量，因为一个类型为父类的变量有可能实际指向的是一个子类的对象。</p>

<p>当调用一个方法时，究竟应该调用哪个方法，这件事情叫做绑定。绑定表明了调用一个方法的时候，我们使用的是哪个方法。绑定有两种：一种是早绑定，又称静态绑定，这种绑定在编译的时候就确定了；另一种是晚绑定，即动态绑定。动态绑定在运行的时候根据变量当时实际所指的对象的类型动态决定调用的方法。Java缺省使用动态绑定。
</p>
<div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">Toniko</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;Toniko</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;wdt***@163.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="https://www.icourse163.org/learn/ZJU-1001542001?tid=1002776001#/learn/content?type=detail&amp;id=1004061166&amp;sm=1">&nbsp;&nbsp;参考地址</a></p></div></span>5年前 (2018-10-13)</div></div></li><!-- #comment-## -->
<li class="comment even thread-even depth-1" id="comment-37886"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;多态</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;176***64709@163.com</p></div><div id="runoobvote-id-37886" data-commid = "37886" class="upvotejs"><a class="upvote"></a> <span class="count">11</span></div></div><div class="comt-main" id="div-comment-37886"><p>如果子类的方法覆盖了父类的方法，我们也说父类的那个方法在子类有了新的版本或者新的实现。覆盖的新版本具有与老版本相同的方法签名：相同的方法名称和参数表。因此，对于外界来说，子类并没有增加新的方法，仍然是在父类中定义过的那个方法。不同的是，这是一个新版本，所以通过子类的对象调用这个方法，执行的是子类自己的方法。</p><p>覆盖关系并不说明父类中的方法已经不存在了，而是当通过一个子类的对象调用这个方法时，子类中的方法取代了父类的方法，父类的这个方法被“覆盖”起来而看不见了。而当通过父类的对象调用这个方法时，实际上执行的仍然是父类中的这个方法。注意我们这里说的是对象而不是变量，因为一个类型为父类的变量有可能实际指向的是一个子类的对象。</p><p>当调用一个方法时，究竟应该调用哪个方法，这件事情叫做绑定。绑定表明了调用一个方法的时候，我们使用的是哪个方法。绑定有两种：一种是早绑定，又称静态绑定，这种绑定在编译的时候就确定了；另一种是晚绑定，即动态绑定。动态绑定在运行的时候根据变量当时实际所指的对象的类型动态决定调用的方法。Java缺省使用动态绑定。</p><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">多态</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;多态</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;176***64709@163.com</p></div></span>4年前 (2018-12-10)</div></div></li><!-- #comment-## -->
<li class="comment byuser comment-author-tianqixin bypostauthor odd alt thread-odd thread-alt depth-1" id="comment-40084"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;runoob</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;826***t351@qq.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="https://blog.csdn.net/trojanpizza/article/details/6556604">&nbsp;&nbsp;参考地址</a></p></div><div id="runoobvote-id-40084" data-commid = "40084" class="upvotejs"><a class="upvote"></a> <span class="count">23</span></div></div><div class="comt-main" id="div-comment-40084"><h3 data-title>JAVA – 虚函数、抽象函数、抽象类、接口</h3>

<p><strong>1. Java 虚函数</strong></p>

<p>虚函数的存在是为了多态。</p>

<p>C++ 中普通成员函数加上 virtual 关键字就成为虚函数。</p>

<p>Java 中其实没有虚函数的概念，它的普通函数就相当于 C++ 的虚函数，动态绑定是 Java 的默认行为。如果 Java 中不希望某个函数具有虚函数特性，可以加上  final 关键字变成非虚函数。</p>

<p>PS: 其实 C++ 和 Java 在虚函数的观点大同小异，异曲同工罢了。</p>
<p><strong>2. Java抽象函数(纯虚函数)</strong></p>

<p>抽象函数或者说是纯虚函数的存在是为了定义接口。</p>

<p>C++ 中纯虚函数形式为：</p><pre>virtual void print() = 0;</pre>

<p>Java 中纯虚函数形式为：</p><pre>abstract void print();</pre>

<p><strong>PS:</strong> 在抽象函数方面 C++ 和 Java 还是换汤不换药。</p>

<p><strong>3. Java 抽象类</strong></p>

<p>抽象类的存在是因为父类中既包括子类共性函数的具体定义，也包括需要子类各自实现的函数接口。抽象类中可以有数据成员和非抽象方法。</p>

<p>C++ 中抽象类只需要包括纯虚函数，既是一个抽象类。如果仅仅包括虚函数，不能定义为抽象类，因为类中其实没有抽象的概念。</p>

<p>Java 抽象类是用 abstract 修饰声明的类。</p>

<p><strong>PS:</strong> 抽象类其实是一个半虚半实的东西，可以全部为虚，这时候变成接口。</p>

<p><strong>4. Java 接口</strong></p>

<p>接口的存在是为了形成一种规约。接口中不能有普通成员变量，也不能具有非纯虚函数。</p>

<p>C++ 中接口其实就是全虚基类。</p>

<p>Java 中接口是用 interface 修饰的类。</p>

<p><strong>PS:</strong> 接口就是虚到极点的抽象类。</p>

<p><strong>5. 小结</strong></p>

<pre>C++ 虚函数&nbsp; &nbsp;&nbsp;==&nbsp; Java 普通函数

C++ 纯虚函数&nbsp; ==&nbsp; Java 抽象函数

C++ 抽象类&nbsp;&nbsp;&nbsp; ==&nbsp; Java 抽象类

C++ 虚基类&nbsp;&nbsp;&nbsp; ==&nbsp; Java 接口</pre><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="../note/40084">runoob</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;runoob</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;826***t351@qq.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="https://blog.csdn.net/trojanpizza/article/details/6556604">&nbsp;&nbsp;参考地址</a></p></div></span>4年前 (2019-02-25)</div></div></li><!-- #comment-## -->
<li class="comment even thread-even depth-1" id="comment-43721"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;yhxf1985</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;yhx***fan@163.com</p></div><div id="runoobvote-id-43721" data-commid = "43721" class="upvotejs"><a class="upvote"></a> <span class="count">6</span></div></div><div class="comt-main" id="div-comment-43721"><p>可以通过抽象类引用指向不同的子类实例，实现动态多态性。</p>

<pre>public class Test {
    public static void main(String[] args) {
      //show(new Cat());  // 以 Cat 对象调用 show 方法
      //show(new Dog());  // 以 Dog 对象调用 show 方法
      Animal a;        
      a = new Cat();    
      a.eat();               
      a.work();        
      a = new Dog();   
      a.eat();               
      a.work();       
      
  }  
            
    public static void show(Animal a)  {
      a.eat(); 
      a.work(); 
    }  
}
 
abstract class Animal {  
    abstract void eat();  
    abstract void work();  
}  
  
class Cat extends Animal {  
    public void eat() {  
        System.out.println("吃鱼");  
    }  
    public void work() {  
        System.out.println("抓老鼠");  
    }  
}  
  
class Dog extends Animal {  
    public void eat() {  
        System.out.println("吃骨头");  
    }  
    public void work() {  
        System.out.println("看家");  
    }  
}</pre><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">yhxf1985</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;yhxf1985</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;yhx***fan@163.com</p></div></span>4年前 (2019-06-18)</div></div></li><!-- #comment-## -->
<li class="comment odd alt thread-odd thread-alt depth-1" id="comment-48721"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;命数如织当为磐石</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;and***_e@163.com</p></div><div id="runoobvote-id-48721" data-commid = "48721" class="upvotejs"><a class="upvote"></a> <span class="count">9</span></div></div><div class="comt-main" id="div-comment-48721"><p>在向上引用时，子类的同名非静态成员方法与成员变量会覆盖父类的同名非静态成员方法和成员变量，子类的同名静态成员方法会被父类的同名静态成员方法隐藏，也就是说被覆盖。</p>

<p>可以通过 super 关键字在子类中显式调用父类中被覆盖的非静态成员方法和成员变量。</p>

<pre>public class Test {
    public static void main(String[] args) {
        System.out.println("Polymorghpic Test");
        Animal a = new Dog();
        Animal b = new Dog("smith", 5);
        // 子类的非静态方法与变量覆盖父类     
        a.getInfo();
        // 子类通过super调用父类的非静态成员方法和变量  
        a.getSuperInfo();
        // 子类的静态方法被父类隐藏   
        a.hello();
        b.getInfo();
        b.hello();
    }
}
class Animal {
    String name;
    int age;
    public Animal() {
        name = "alex";
        age = 1;
    }
    public Animal(String nm, int ag) {
        name = nm;
        age = ag;
    }
    public void getInfo() {
        System.out.print(name + "'s age is " + age + '\n');
    }
    public void getSuperInfo() {}
    public static void hello() {
        System.out.println("Greeting from Animal");
    }
}
class Dog extends Animal {
    String name;
    int age;
    public Dog() {
        name = "prter";
        age = 3;
    }
    public Dog(String nm, int ag) {
        super(nm, ag);
    }
    public void getInfo() {
        System.out.print(name + "'s age is " + age + '\n');
    }
    // 通过super显式调用父类的非静态成员方法   
    public void getSuperInfo() {
        super.getInfo();
    }
    public static void hello() {
        System.out.println("Greeting from Dog");
    }
}</pre>
结果：

<pre>Polymorghpic Test
prter's age is 3
alex's age is 1
Greeting from Animal
null's age is 0
Greeting from Animal</pre><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">命数如织当为磐石</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;命数如织当为磐石</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;and***_e@163.com</p></div></span>3年前 (2019-11-23)</div></div></li><!-- #comment-## -->
<li class="comment even thread-even depth-1" id="comment-49940"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;bluelich</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;blu***ch@sina.cn</p></div><div id="runoobvote-id-49940" data-commid = "49940" class="upvotejs"><a class="upvote"></a> <span class="count">15</span></div></div><div class="comt-main" id="div-comment-49940"><p>静态方法被子类重写，要看父类引用还是子类引用指向子类对象，如果是父类引用指向子类对象，那么调静态方法时，会调用父类的静态方法，如果是子类引用指向子类对象，那么调静态方法时，会调用子类的静态方法。</p>


<pre>public class Test {
    public static void main(String[] args) {
        System.out.println("Polymorghpic Test");
        Animal a = new Dog();
        Animal b = new Dog("smith", 5);
        Dog c = new Dog();
        // 子类的非静态方法与变量覆盖父类
        a.getInfo();
        // 子类通过super调用父类的非静态成员方法和变量
        a.getSuperInfo();
        // 子类的静态方法被父类隐藏
        a.hello();
        b.getInfo();
        b.hello();
        // 调用子类的静态方法
        c.hello();
    }
}

class Animal {
    String name;
    int age;
    public Animal() {
        name = "alex";
        age = 1;
    }

    public Animal(String nm, int ag) {
        name = nm;
        age = ag;
    }

    public void getInfo() {
        System.out.print(name + "'s age is " + age + '\n');
    }

    public void getSuperInfo() {}
    public static void hello() {
        System.out.println("Greeting from Animal");
    }
}

class Dog extends Animal {
    String name;
    int age;
    public Dog() {
        name = "prter";
        age = 3;
    }

    public Dog(String nm, int ag) {
        super(nm, ag);
    }

    public void getInfo() {
        System.out.print(name + "'s age is " + age + '\n');
    }

    // 通过super显式调用父类的非静态成员方法
    public void getSuperInfo() {
        super.getInfo();
    }

    public static void hello() {
        System.out.println("Greeting from Dog");
    }
}</pre>


<p>输出结果：</p>


<pre>Polymorghpic Test
prter's age is 3
alex's age is 1
Greeting from Animal
null's age is 0
Greeting from Animal
Greeting from Dog</pre><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">bluelich</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;bluelich</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;blu***ch@sina.cn</p></div></span>3年前 (2020-01-09)</div></div></li><!-- #comment-## -->
	</ol>
	<div class="pagenav">
			</div>
</div>
<div id="respond" class="no_webshot"> 
		<div class="comment-signarea" style="display:none; padding: 20px 20px;"> 
	<h3 class="text-muted" id="share_code" style="color: #799961;"><i class="fa fa-pencil-square-o" aria-hidden="true"></i> 点我分享笔记</h3>
	<!--
	<p style="font-size:14px;">笔记需要是本篇文章的内容扩展！</p><br>
	<p style="font-size:12px;"><a href="../tougao" target="_blank">文章投稿，可点击这里</a></p>
	<p style="font-size:14px;"><a href="../w3cnote/runoob-user-test-intro.html#invite" target="_blank">注册邀请码获取方式</a></p>
		<h3 class="text-muted"><i class="fa fa-info-circle" aria-hidden="true"></i> 分享笔记前必须<a href="javascript:;" class="runoob-pop">登录</a>！</h3>
		<p><a href="../w3cnote/runoob-user-test-intro.html#invite" target="_blank">注册邀请码获取方式</a></p>-->
	</div>
		
	<form action="/wp-content/themes/runoob/option/addnote.php" method="post" id="commentform" style="display:none;">
		<div class="comt">
			<div class="comt-title">
				<i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i>				<p><a id="cancel-comment-reply-link" href="javascript:;">取消</a></p>
			</div>
			<div class="comt-box">
			<div id="mded"></div>
			
				<div class="comt-ctrl">
					<div class="comt-tips"><input type='hidden' name='comment_post_ID' value='5027' id='comment_post_ID' />
<input type='hidden' name='comment_parent' id='comment_parent' value='0' />
</div>
					<button type="submit" name="submit" id="submit" tabindex="5"><i class="fa fa-pencil" aria-hidden="true"></i> 分享笔记</button>
				</div>
			</div>
		
				
					<div class="comt-comterinfo"> 
						<ul id="comment-author-info">
							<li class="form-inline"><label class="hide" for="author">昵称</label><input class="ipt" type="text" name="author" id="author" value="" tabindex="2" placeholder="昵称"><span class="text-muted">昵称 (必填)</span></li>
							<li class="form-inline"><label class="hide" for="email">邮箱</label><input class="ipt" type="text" name="email" id="email" value="" tabindex="3" placeholder="邮箱"><span class="text-muted">邮箱 (必填)</span></li>
							<li class="form-inline"><label class="hide" for="url">引用地址</label><input class="ipt" type="text" name="url" id="url" value="" tabindex="4" placeholder="引用地址"><span class="text-muted">引用地址</span></li>
						</ul>
					</div>
				
			
		</div>

	</form>
	</div>
<script type="text/javascript">
$(function() {
	//初始化编辑器
	
	var editor = new Simditor({
	  textarea: $('#mded'),
	  placeholder: '写笔记...',
	  upload:false,
	 // upload: {url:'/api/comment_upload_file.php',params: null,fileKey: 'upload_file',connectionCount: 1,leaveConfirm: '文件正在上传，您确定离开?'},
	  defaultImage: 'https://www.runoob.com/images/logo.png',
	  codeLanguages: '',
	  autosave: 'editor-content',
	  toolbar: [  'bold','code','ul','ol','image' ]
	});
	editor.on('selectionchanged', function() {
		$(".code-popover").hide();
	});

	// 提交数据
	$("#share_code").click(function() {
		$(".comment-signarea").hide();
		$("#commentform").show();
		
	});
	$("#user_add_note").click(function() {
		$(".comment-signarea").hide();
		$("#commentform").show();
		$('html, body').animate({
       	    scrollTop: $("#respond").offset().top
    	}, 200);
	});

	// 提交笔记
	var commentform=$('#commentform');
	commentform.prepend('<div id="comment-status" style="display:none;" ></div>');
	var statusdiv=$('#comment-status');
	
	commentform.submit(function(e){
		e.preventDefault();
		var noteContent = editor.getValue();
		// console.log(noteContent);
		noteContent = noteContent.replace(/<pre><code>/g,"<pre>");
		noteContent = noteContent.replace(/<\/code><\/pre>/g,"</pre>");
		
		// 系列化表单数据
		var comment_parent = 0;
		var is_user_logged_in = $("#is_user_logged_in").val();
		var comment_post_ID =  5027;
		var _wp_unfiltered_html_comment = $("#_wp_unfiltered_html_comment").val();
		var comment = noteContent;
		var author = $("#author").val();
		var url = $("#url").val();
		var email = $("#email").val();
		if(isBlank(author) && is_user_logged_in==0) {
			statusdiv.html('<p  class="ajax-error">请输入昵称！</p>').show();
		} else if(isBlank(email)  && is_user_logged_in==0) {
			statusdiv.html('<p  class="ajax-error">请输入邮箱！</p>').show();
		} else {
			// var formdata=commentform.serialize() + "&comment=" + noteContent ;
			// 添加状态信息
			statusdiv.html('<p>Processing...</p>').show();
			// 获取表单提交地址
			var formurl=commentform.attr('action');
			
			// 异步提交
			$.ajax({
					type: 'post',
					url: formurl,
					dataType:'json',
					data: {"comment_parent":comment_parent,"comment_post_ID":comment_post_ID, "_wp_unfiltered_html_comment":_wp_unfiltered_html_comment,"comment":comment,"url":url, "email":email,"author":author},
					error: function(XMLHttpRequest, textStatus, errorThrown){
					statusdiv.html('<p class="ajax-error" >数据不完整或表单提交太快了！</p>').show();
				},
				success: function(data, textStatus){
					if(data.errorno=="0") {
						$("#submit").prop('disabled', true);
						statusdiv.html('<p class="ajax-success" >笔记已提交审核，感谢分享笔记！</p>').show();
						alert('笔记已提交审核，感谢分享笔记！');
					}else{
						statusdiv.html('<p class="ajax-error" >'+data.msg+'</p>').show();
					}
					commentform.find('textarea[name=comment]').val('');
				}
			});
			setTimeout(function(){
		        $("#submit").prop('disabled', false);
		    }, 10*1000);
		}
		return false;

	});
	$(".comt-author").click(function() {
		href = $(this).children("a").attr("href");
		if(href.indexOf("/note/")!=-1) {
			var win = window.open(href, '_blank');
  			win.focus();
		}
	});
	$(".comt-meta span").hover(function(){
		$(this).children(".tooltip").css({ "opacity": 1, "pointer-events": "auto"});
	},function(){
		$(this).children(".tooltip").removeAttr("style");
	});
	/*
	$(".wrapper i").hover(function(){
		$(this).siblings(".tooltip").css({ "opacity": 1, "pointer-events": "auto"});
	},function(){
		$(this).siblings(".tooltip").css({ "opacity": 0, "pointer-events": "auto"});
	});
	*/
	//Upvote.create('runoobvote-id', {callback: vote_callback});
	var ajaxurl = 'https://www.runoob.com/wp-admin/admin-ajax.php';
	var callback = function(data) {
		//console.log($('#runoobvote-id').upvote('upvoted'));
		//console.log($('#runoobvote-id').upvote('downvoted'));
		//console.log(data);
		_vote_action = data.action;
		id_arr = data.id.split('-');
		um_id= id_arr[2];
		//console.log(um_id);
		
		var re = /^[1-9]+/;
		if (re.test(um_id)) { 
			var ajax_data = {
				_vote_action: _vote_action,
				action: "pinglun_zan",
				um_id: um_id,
				um_action: "ding"
			};
			//console.log(ajax_data);
			$.post(ajaxurl,ajax_data,function(status){
				//if(status.vote_num>999) {
				//	_voteHtml = '<span style="display: block; text-align: center;font-size: 20px; color: #6a737c; margin: 8px 0;">'+kFormatter(status.vote_num) +'</span>';
				//	$("#runoobvote-id-" + um_id + " .count").hide().after(_voteHtml);
				//}
				
			});
		}
	};
	if($('#comments').length && $('.upvotejs').length){
		$('.upvotejs').upvote({id: 5027, callback: callback});
	
		$.post(ajaxurl,{"action":"pinglun_zan","postid":5027},function(data){  
			$(data).each(function(key,value) {
				$("#runoobvote-id-" + value.commid + " .upvote").addClass(value.upvotejs_class);
				$("#runoobvote-id-" + value.commid + " .downvote").addClass(value.downvote_class);
				$("#runoobvote-id-" + value.commid + " .count").text(value.upvote_count);
			})
		},'json');
		
	}
	
	
});
function isBlank(str) {
    return (!str || /^\s*$/.test(str));
}
function kFormatter(num) {
	// return num;
    return Math.abs(num) > 999 ? Math.sign(num)*((Math.abs(num)/1000).toFixed(1)) + 'k' : Math.sign(num)*Math.abs(num)
}

</script>

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